MySql Подготовлено заявление для преобразования значения строки в Колонном

Question

Я пытаюсь следовать примеру с этого сайта: http://vitobotta.com/mysql-generate-column-names-dynamically-from-row-values/

У меня есть таблица вроде этого:

+------------+--------------+----------+-------------+ 
| MessageId | ProcessDate | FieldName | FieldValue | 
+------------+--------------+-----------+------------+ 
|   18 | 2015-12-04 | data  | 101110101 | 
|   18 | 2015-12-04 | type | binary  | 
|   19 | 2015-12-04 | type | integer | 
|   19 | 2015-12-04 | data  | 34   | 
+------------+--------------+-----------+------------+ 

То, что я хочу что-то как это:

+------------+--------------+----------+-------------+ 
| MessageId | ProcessDate | type  | data | 
+------------+--------------+-----------+------------+ 
|   18 | 2015-12-04 | binar | 101110101 | 
|   19 | 2015-12-04 | integer | 34   | 
+------------+--------------+-----------+------------+ 

Мой код:

DROP TABLE IF EXISTS tmp_results; 

CREATE TEMPORARY TABLE tmp_results AS 
SELECT r.`MessageId`, r.`ProcessDate`, r.`TransportType`, d.`FieldName`, d.`FieldValue` 
FROM 
returnmessages r, decodedmessagessummaryrecord s, decodedmessagesdetailrecord d 
WHERE r.`Id` = s.`ReturnMessagesId` 
AND s.`Id` = d.`DecodedMessagesSummaryRecordId` 
AND r.`MobileId` = "35" 
LIMIT 10; 

SELECT CONCAT(' 
    SELECT MessageId, ProcessDate, TransportType, ', field_value, ' 
    FROM tmp_results' 
) 
INTO @variable1 
FROM 
(SELECT GROUP_CONCAT(CONCAT('IFNULL(MAX(CASE WHEN FieldName=''',field_name,''' THEN FieldValue 
END), ''-'' AS "', col_name,'"')) field_value 
FROM(
    SELECT field_name, field_name as col_name 
    FROM(SELECT DISTINCT FieldName AS field_name FROM tmp_results) AS fieldnames 
) field_with_col_names 
) result; 
PREPARE prepstate FROM @s; 

EXECUTE prepstate; 

DEALLOCATE PREPARE prepstate; 

который возвращает ошибку:

Error Code: 1064. You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'FROM tmp_results' at line 3

Я не совсем уверен, что это происходит не так в этой точке.

Answer 1

SELECT 
    GROUP_CONCAT(DISTINCT 
    CONCAT(
     'max(case when FieldName = ''', 
     FieldName, 
     ''' then FieldValue end) AS ', 
     '`',FieldName,'`' 
    ) 
) INTO @sql 
from tmp_results; 

SET @sql = CONCAT('SELECT MessageId, ProcessDate, TransportType, ', @sql, ' from tmp_results 
group by MessageId'); 

SELECT @sql; 
PREPARE stmt FROM @sql; 
EXECUTE stmt; 
DEALLOCATE PREPARE stmt; 

FIDDLE